Question
What is the vapor pressure of a aqueous solution containing 10 % (by weight) ethylene glycol (62 g/mol) at 25 °C. PH2O = 24.3 torr at 25°C?
Answers
DrBob222
10% w/w means 10 g ethylene glycol per 100 g solution.
mols ethylene glycol = grams/molar mass
10g eth/(90g H2O + 10g eth)
mols in 90g H2O = grams/molar mass
total mols = mols ethylene glycol + mols H2O
Then XH2O = mols H2O/total mols.
Psoln = XH2O*P<sup>o</sub><sup>H2O<sup>
mols ethylene glycol = grams/molar mass
10g eth/(90g H2O + 10g eth)
mols in 90g H2O = grams/molar mass
total mols = mols ethylene glycol + mols H2O
Then XH2O = mols H2O/total mols.
Psoln = XH2O*P<sup>o</sub><sup>H2O<sup>
Addison
23.5 torr